Tibetan monks at a ceremony in Qinghai province. Tibetan rights activists have expressed outrage at China jailing monk and author Gartse Jigme for five years. Photograph: Reinhard Krause/Reuters

Tibetan rights groups have reacted with outrage after Chinese authorities sentenced a Tibetan monk to five years in prison for criticising the Chinese government.

Gartse Jigme, 36, was sentenced on 14 May by a county court in Malho, a prefecture in western Qinghai province bordering the Tibetan autonomous region. Jigme, a monk at Gartse monastery in the mostly Tibetan county of Rebkong, has been a writer since 1999, according to rights groups. He has been in detention since 1 January.

"The distribution of his book Courage of the King was cited as a reason for his detention," an unnamed source told Radio Free Asia. The book covers topics Tibetans are not allowed to openly discuss, such as the Dalai Lama, protests, and self-immolation.

According to Tibetan rights groups, 117 Tibetans have self-immolated since February 2009 to protest Chinese rule over the Himalayan region.

"This is really outrageous, because [Jigme] was not involved in any criminal activities at all," said Tsering Tsomo, executive director for the Tibetan Centre for Human Rights and Democracy in Dharamsala, India, home of the self-declared Tibetan government in exile. "He just wrote a book – this was just a form of peaceful resistance against the government."

Jigme was arrested soon after finishing the second volume of Courage of the King, an outspoken work aimed at Beijing for its policies in Tibet. Exiled Tibetans in India published the volume – which calls the Chinese government "evil," "blind" and "dictatorial" – soon after he was sentenced.

Tsomo called Jigme's voice "one of the most courageous to come out of Tibet".

"These people, they know that when they write these things, they know that they're going to jail," she said. "They know that, but they do it anyway."

"The truth is that no particular organisation or lama instigated the martyrs to commit self-immolations," Jigme wrote in the book, according to a translation by the Tibetan Centre for Human Rights and Democracy. "They were motivated by the sufferings and aspirations of their fellow six million Tibetans."